Autofocus
Nikkor 24-85mm f/3.5-4.5 IF-ED AF-S Review

An
AF-S lens for significantly less than US$400?

The
small size of this lens makes it a perfect partner for the
modest-sized bodies, such as the D100 (shown here) or the
F100. Even on the smaller bodies (N65, N75, N80) the lens
still seems modest in size. This picture, by the way, shows
the lens fully extended.

Lens
Formula

15
elements/12 groups; 1ED element.

Filter
Thread

67mm

Close
Focus

1.2
feet (.38m)

Angle
of View

22°54'-71°18'
with 35mm, 18°48'-60°54'
with D1

Other
Features

hood provided, AF/MF switch, 7-blade aperture

Weight

14.6
ounces (415g)

Price

US$350
(street)

The
Basics

"Unbelievable"
was what everyone thought when they first saw the US$350 street
price of this lens. But then they noticed the specifications: G-type
with no aperture ring and a slow variable aperture. "Oh, that's
the catch," they decided, and immediately dismissed the lens.
Not so fast, I say. This is a respectable lens with a few very nice
things going for it, as you'll see shortly.

I've
never been a fan of the mid-range zoom, let alone Nikon's interpretations
of it. The 35-70mm f/2.8 could be the sharpest zoom Nikon has made,
but it's big and heavy and features a focal length range that is
very limited. The 28-70mm f/2.8 AF-S is even bigger and heavier,
but at least gives you a more useful angle of view at the wide end.
In the consumer realm, we have the abysmal 28-80mm f/3.3-5.6G and
28-100mm f/3.5-5.6G, the adequate 24-85mm f/2.8-4D and 24-120mm
f/3.5-5.6D, and the pretty decent 28-105mm f/3.5-4.5D. But none
of these lenses ever made it into my bag on a permanent basis. For
a mid-range zoom to make it into use in my rotation it needs to
give me at least 24mm at the wide end, fast focus, sharp optics,
and it must be able to fit into one of the short slots of my Lowe
Pro Trekker. Of the aforementioned lenses, only the 28-105mm comes
close. But 28mm isn't wide enough for me, especially now that I'm
shooting digital.

Thus,
I looked at the 24-85mm AF-S with interest when it was introduced,
and decided to give it an extended tryout at some of my recent workshops.

This
Nikkor has a variable maximum aperture that ranges from f/3.5 at
24mm to f/4.5 at 85mm. The minimum aperture is f/22 at the wide
end, f/29 at 85mm. Since this is a G-type lens, there is no aperture
ring. (G-type lenses are basically D-type lenses without an aperture
ring.) Focusing can be as close as 1.2 feet (.38m) at any zoom setting.
No depth of field or infrared focus index marks are provided. The
IF in the name indicates that it is an internal focus lens, meaning
the front element does not rotate during zoom or focus. The ED indicates
that one of the elements is made of Nikon's unique extra-low dispersion
glass. As with all ED lenses, the lens focuses past infinity under
normal temperature conditions.

The
manual zoom and focus rings are separate, and easily distinguished.
Curiously, the focus ring is the one closer to the camera (the zoom
ring is at the front of the lens). The lens uses 67mm accessories,
which is a hassle, as Nikon's standards for most lenses are 62mm
or 77mm. That means you'll probably want to pick up a 67-77mm step-up
ring if you use other serious Nikon optics. There are 15 elements
in 12 groups. One of those elements is a compound aspherical element,
while another is ED glass. The lens formula is about average in
number of elements for a modern aspherical design.

The
lens comes with the HB-28 hood, but you'll have to pony up extra
cash for the optional soft lens pouch (CL-S2). Nikon claims that
the lens is incompatible with all teleconverters, but given the
slow maximum aperture, I doubt you'd want to use one, anyway.

The
size is small: about 72.5mm in overall length and 73mm in diameter.
Build quality is mostly plastic and not the textured metal you're
probably used to with other AF-S lenses.

How
sharp is this lens? Well, at the left is a handheld shot at
85mm, f/4.5 (!) and 1/60 second. Below, the detail at 100%.
Actually, some of the blur in the close-up below is due to
the chameleon moving during the exposure (the eye, for example).
Look at the darker plate just behind the eye where the cursor
is). This photo is sharp. And remember, this is at 85mm at
nearly the minimum focus distance and wide open!

Handling

The
focus and zoom rings are easily distinguished, but reversed from
what you're probably used to. This makes the lens feel "foreign"
the first few times you use it (well, maybe always if you
keep switching between this and other Nikkor zooms where the rings
are "normal"). The zoom ring is a bit stiff, not quite
the equal of the professional lenses. The focus ring is decent,
but has the usual autofocus "looseness." Both the focus
and zoom go from one extreme to the other in about a quarter of
a turn.

The
front element is not recessed, and the supplied hood isn't particularly
deep, so it's easy to accidentally touch the glass or bump it
against something, so be careful where you point the camera. The
rear element is recessed at most zoom settings, but it, too, is
exposed when the lens is zoomed to 24mm. You might want to zoom
in prior to removing the lens from the camera.

The
butterfly-style lens hood bayonets onto the front piece, and as
is usual, is made of cheap, flexible, plastic. Getting the bayonet
lined up is helped by a small white dot on both parts. Unfortunately,
you won't see the dot on the lens unless you're behind the camera--if
you try to put the bayonet on from the front, you can't see the
alignment mark. On the plus side, you can leave the hood on and
get the lens cap on and off if you have small fingers.

If
you've got a body with an internal flash, be aware that the lens
cuts off some of the light from the flash at anything wider than
28mm, especially when the hood is on.

As
with all AF-S lenses, you can manually override autofocus at any
time. The lens also has an easy-to-find AF/M switch if you want
to turn off the autofocus on the lens. One thing that struck me
as strange is that, when fully extended, there's a bit of side-to-side
play to the front-most element. I haven't noticed any optical
problems due to this, but it isn't confidence inspiring (nor is
it something I've seen on any other Nikkor).

There
are some handling limitations that interfere with the use of the
lens on some cameras:

N90s,
F4, N70, N8008, and N6000 users: Aperture priority and manual
priority exposure modes aren't available (you have no way to
set an aperture!).

F3AF,
N6006, N2020, and all manual focus bodies (except the N6000):
All
exposure modes are unavailable. Essentially you can use the lens
at its given aperture and use an external metering system.

.

Performance

I
was prepared to be disappointed with this lens. Instead, I've decided
to keep in my bag and use it regularly. Remember, I don't say that
about the 28-70mm or 35-70mm AF-S lenses. (Why? Because both are
large lenses with very small focal length ranges--you don't get
a lot of flexibility with them, so I don't find using them much
more convenient than having a 35mm, 60mm, and 85mm lens in my bag.
And, as good as the modern zooms are, they're no match for the
fixed lenses.)

Focusing
is eerily silent and AF-S fast. Because of the slower, variable
aperture, I was expecting to see some compromise here, but if the
camera body can calculate the focus point, this lens will reach
it nearly instantaneously, with no hunting. Even on the CAM900 sensor
of the N65, N75, N80, D100, Kodak Pro 14n, and Fuji S2 Pro, this
lens focuses fast and reliably. Whatever compromises Nikon made
to keep the lens in the affordable range, focus speed wasn't one
of them.

On
a digital body from 24 to 85mm, from corner to corner, this lens
turns in some impressive results, especially considering its price.
I see little obvious to complain about other than a small amount
of linear distortion at both extremes. Compared to the older 24-85mm
f/2.8-4, the newer AF-S lens simply is in another (higher) class.
On a full-frame body, you can see light falloff and loss of sharpness
in the corners, but not nearly as much as I would have expected,
considering the price. Optically, on a digital body this lens is
excellent, while on a full frame body it still rates very good.

Flare
hasn't been a problem, especially when the supplied lens hood is
used.

There's
less barrel distortion than I expected at the widest focal length,
but it's still there. Stick a horizon towards the top or bottom
of the frame and you'll get a very slightly curved line.

While
the lens focuses down to 1.2 feet at every focal length, this isn't
a macro lens, and the results show that. When used at the close
extreme at 85mm, for example, the results on my sample aren't quite
as sharp and contrasty as they are at longer distances. You have
to look carefully at prints to see the difference, but it's there.

Overall,
the 24-85mm AF-S is an optical bargain from Nikon: sharp, crisp
images that are obtained with fast, sure focus usually command double
or triple the price in the Nikkor lineup.

Drawbacks

Build.
Not a professional build, no aperture ring. Still, it's solid,
and the focus and zoom rings are smooth, if not silky.

Filter
Size. 67mm? What was Nikon thinking?.

Zoom
and Focus rings are reversed. The lens feels "wrong"
when you first go to zoom.

No
depth of field scale. We don't even get cut-out
depth of field charts in the manual, let alone anything on the
lens. At least give us one set of markings for the widest angle,
Nikon.

Now
that Nikon has also issued the revised 24-120mm with VR, many are
asking whether they should get that lens instead. I prefer the 24-85mm
AF-S. Here's the drawbacks of the 24-120mm:

Slow
apertures. f/5.6 comes quickly on the 24-120mm, and
that pushes the autofocus performance of the CAM900 cameras
using the outboard sensors. Moreover, it makes for a dim viewfinder
and not nearly enough depth of field control above 80mm.

Not
as sharp. At
least in the initial samples I've seen and used, the 24-120mm
isn't as sharp at 24mm, especially on full-frame bodies. The
VR appeals to the folks that think that tripods aren't necessary,
but frankly, if you have to rely upon VR for everyday photography,
you don't have good enough technique. VR is a godsend for shooting
from vehicles and other situations where technique can be compromised,
but it is not a substitute.

More
expensive. While
the 24-120mm isn't an expensive lens, it is more expensive than
the 24-85mm by a good chunk of change. Enough to buy a flash
or other accessory. Is there really something about the 24-120mm
that you need? For most people, probably not.

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